Which contemporary researcher had coined the acronym LASER before Maiman built the working model?
Gordon Gould
While Theodore Maiman is recognized for achieving the first practical, working demonstration of the device, the nomenclature associated with it was established earlier by Gordon Gould. Gould was actively working on gas lasers and is specifically credited with coining the acronym LASER, which stands for Light Amplification by Stimulated Emission of Radiation, sometime prior to Maiman's breakthrough. Although Gould had the terminology and theoretical concepts, Maiman's successful construction and demonstration of a working model using a solid-state ruby material in 1960 provided the tangible evidence that validated the physics, quickly outpacing the theoretical work.

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The world's first laser was successfully operated by Theodore Maiman